[stable-1] Fix docker tests (#1398)

* Adjust version_added, re-place tests. (#34)

* Template docker test containers.

* Forgot to adjust test.

tests/integration/targets/docker_host_info/tasks/test_host_info.yml

@@ -28,7 +28,7 @@
 # * network list is always non-empty (default networks).
   - name: Create container
     docker_container:
-      image: alpine:3.8
+      image: "{{ docker_test_image_alpine }}"
       command: '/bin/sh -c "sleep 10m"'
       name: "{{ cname }}"
       state: started